Starting mechanism for internal-combustion engines.



G. C. DAWSON & I.

W. ANDERSON. STARTING MECHANISM FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED FEB. 2. 1915. 1,157,849.

MHZ E8859 w Patented Oct. 26, 1915..-

"UNITED STATES PATENT OFFICE.

GREGomi c. DAVISON AND JOHN w. VANDERSON, OF-NEW LQNDON, CONNECTICUT, AssIGNoRs T0 ELECTRIC BOAT cmvrPAwY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

STARTING MECHANISM FOR INTERNAL- COMBUSTION ENGINES.

T0 all whom it may concern: 1

Be it known that we, GREGORY DAVI- SON and JOHN T. ANDERSON, citizens of the United States, residing at New London, in the county of New London and State of Connecticut, have invented certain new and Specification of Ihetters Patent.

Application filed February 2, 191's. Serial No. 5,604.

useful Improvements in Starting Mechanism for Internal-Combustion Engines; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to'make and use the same.

This invention relates to starting mechanism for internal combustion engines of the type employing compressed air as the starting medium, such air being admitted to the cylinders of the engine to act on the pistons therein. I

The object of the invention is to provide such a starting mechanism employing pneumatically actuated air-inlet valves onthe cylinders of the engine controlling the admission of compressed air to the cylinders and a simple form of valve mechanism governing the supply of the actuating air to these pneumatically actuated valves, this valve mechanism requiring but a single cam to actuate it and being adapted for use in starting the engine in either direction.

4 In accordance with the invention, each of a plurality of the cylinders of the engine is provided with a pneumatically actuated, air-inlet valve adapted when open to connect the cylinder on which it is mounted With'the source of supply of compressed air. The several inlet valves are connected to a distributer consisting of a plurality of valves which may be mechanicallyiactuated to ad mit air 'to or permit its exhaust from the corresponding inlet valve so as to open or close the latter. These valves of the distributerare arranged radially about a-cam driven by the shaft of the engine so=that they may be actuated by the cam succes sively in the requisite order and with the requisite time intervals between. The manner of mounting the cam or the several valves with which the cam coacts is such as to permit of varying the angular relation of the cam or the valves to the shaft of the engine so as to permit of adapting the starting mechanism for starting the engine Patented Oct. 2c, ais.

in either direction. Preferably, this is done by connecting thecam to the shaft which drives it by means of an axially movable slccve whose connection to one of the two coacting parts is made by means of a spiral thread. The several valves actuated by the :am are of a special construction involving various features of novelty including means whereby these valves are normally hcld out of engagcn'ient with the cam but are automatically moved into engagement with the :am when the source of supply of compressed air is connectcd to the engine for starting the latter. These and other features ofthe invention will be better under-s1 ood by reference to the following description talren in connection with the accompanying drawings, which vention.

In these drawings, Figure 1- is an elevation of :1V portion of an internal combustion show the preferred embodiment of the in-v engine, Fig. 2 is'an elevation, broken away :ployed on each of the cylinders.

Referring to these drawings, Fig. 1 illustrates an internal combustion engine having a plurality of cylinders, three of the cylinders being shown in the figure. The engine is adapted to be started by admitting compressed air to some or all of the cylinders and for this purpose each of a plurality of cylinders 7 is provided with an inlet valve 5 by which air is admitted to the interior of the cylinder. Thisair is supplied through a pipe 6'whichleads from a source of supply of compressed air and which is connected through ducts inthe cylinder'heads to each of the inlet valves 5. The valves 5 are arranged to be actuated pneumatically. For this purpose aconstruction such as-is shown in Fig. 4 maybe em ployed. By reference to that figure, it Will be seen that the cylinder casting 7'is-1prothe rear of the movable member 10. As:

shown in Fig. 4, the part 9 of thecasing for the valve has a plurality of openings therein for the entrance of air from the compressed air pipe, the flow of the compressedair from the pipe through these openings and into the cylinder being controlled by the movable valve member 12. This valve member is opened by admission of air to the upper end of the movable member 10 through the passage 14 and when the pas sage 14 is connected to the atmosphere, the movable member 10 is returned to its initial position by the spring 11, thus closing the valve 12. i

The admission of compressed air to the passages 14 of the several inlet valves so as to open those valves the proper length of time and in the proper sequence, is effected by a distributer Whose movable member is driven by theshaft ,of the engine. This distributer is shown in detail in Figs. 2 and 3 and is shown mounted upon the casing 15 of the engine in Fig. 1. It may be mounted I 1n any position convenient for manipulation and inspection and for connecting it to the engine shaft. This distributor consists of a plurality of valve mechanisms, each connected to a source of supply of compressed air and to one of the inlet valves 5 and a cam driven by the engine shaft and arranged to equal -distances apart.

actuate the several valve mechanisms successively. In the drawings, the cam 16 is shown as mounted upon a shaft 17 supportedin a suitable bearing in the casing 15 of the engine and carrying a gear 18 which meshes with a gear 19 on the engine shaft. I

It will be Tunderstood, however, that any other suitable driving means for the cam, suitably timed withrespect to the engine shaft, may be adopted instead of that shown. Encircling the cam 16 is an annular suppprt 20 having a plurality of valve mechanlsms which are mounted thereon at Each valve mechanism is provided; with a suitable device, such .for instance, as a roller 21 adapted to engage the periphery of the cam 16 so that the cam mayactuate the valve. Each valve mechanism consists of a cylindrical casing 22 having an axial opening therethrough, one portion of which is substan ially larger than the other portion. This opening is adapted to receive a movable valve member 23 which is movable to ositions on one side'and on the other side 0 a port 24 Below this port is another port 25 open tothe atmosphere.

The" stem 26 of the valve member 23 is extended above and below the valve member. Below the valve member it is provided with an enlargement 27 which serves as a guide movable in an opening in the support 20 and which carries the roller 21. Above the valve member 23, the stem 26 is provided with a head 28 and a spring 29 is coiled around the stem 26-between the head 28 and the wall formed by the contraction of the size of the opening in the casing 22. This enlarged portion of the openin in casing 22 is provided with a port 30.

he ports 30 of each of the several valve mechanisms grouped about the cam 16, are connected to the source of supply of compressed air by pipe 31. The ports 24 of the several valve mechanisms are connected by pipes 32, 33 and Eli-to the passages 14 of the air-inlet valve 5.

The cam 16 is so mounted upon its shaft 17 as to permit ofmoving it angularly about the shaft 17 as; desired and when the desired position of the cam has been selected it may be maintained in that angular position with reference to the shaft 17 thr hout the operation'of the engine and c 159.- quent rotation of shaft 17. For this purpose an axially movable sleeve is provided between the cam and the shaft, its connection to one of the two parts being made bya spiral thread. Thissleeve is shown at 35. It is splined to the shaftxl? by means of the keys 36. On its exterior surface are a plurality of spirally arranged threads which are received in corresponding grooves in the opening through the hub 37 of the cam 16. The sleeve-535 ma .bemoved axially as desired, either manua ly, pneumatically or in any other suitable manner. In the drawings, a hand lever is shown for this purpose at 38, this being pivotally mounted upon the casing of the; engine and connected to the sleeve 35 by means of'a short shaft 39. On the end of this short shaft is cured a collar40 and a similar collar -ll 18 secured to the sleeve. 35 by means of a flanged collar 42. Between the collars 40 and 41' are a plurality of balls 43. I

The operation of the mechanism thus constructed will now be described. When the engine is not in use and when the engine is in normal operation, the several valve mechanisms are held from contact with the cam 16, which'is rotated in accordance with the rotation of the engine shaft, the springs 29 serving to move the valve members 23 slightly so as to lift the rollers 21 from engagement with'the cam. When it is desired 1 connected to the ports 30. The air so admitted through the ports 30 acts upon the upper surfaces of the valve members 23 so as to move those valve members and the distances, so that its valve memher gine in'the opposite direction,

lwith the cam 16. In the raise of-most of the valve mechanisms, thisinward movement of the valve member 23 will be very slight since themovement'vvill be arrested by contact of the ro ller '21 with the periphery of the cam 16. One of the valve mechanisms, liloavefter, will he in the position for coaction with the cutaway portion of the cam ltl and tl'iat one will he moved inwardly a greater 2:; will he moved past the 1 't 24. This will perwit the flow of air l'rointhe source of supply through the pipes 31, port 30, the central opening in casing 22, port 52 and the pipe 32, 33 or 34 leading to the inlet valve of the corresponding cylinder and that valve will be actuated so as to admit co npressed air from the conduit G to the corresponding cylinder. The air thus admitted to the cylinder will act on the piston therein to start the rotation of the engine shaft and as the latter so rotates, the cam 16 will he turned, thus carrying the cutaway portion of the cam around into coaction with the roller (if-another valve mechanisnnresulting in the admission of compressed air a to another of the cylinders. As the cutaway portion of the cam passes beyond one of rollers "21, that roller and the parts to which it is connected are moved outwardly as to carry the corr'espondi re member to a position between th This closesthe passage tor members out of coaction ivithfthe cam ltl.

l l'hcnever it is desired to operate the enthe sleeve 35 moved axially by means ot the handle 38,

thus 'tiiriiing the cam 16 about the shaft 17 through definite angular distance so that the cam 16 assinnes a different angular po sition with relation to the shatt of the engine. llhen the admission of air to the c vl iialers of the engine in the numnerahove 1h scribed will cause operation of the engine in the reverse direction.

it will be understood that the distributor may he provided with any desired number of valve mechanisms, but all or a number compressed air to the inlet, valve previv \7 less than all of these may he used desired is it is common to employ internal cornbustion engines having six cylinders, the distrihuter is illustrated as having six valve mechanisms, but it is only necessary to adinit compressed air to three of the cylinders in order to start the engine. If this hefllone, v

the three valve mechanisms corresponding to the three cylinders which are not to be employed in startine may he disconnected. By this construction, a single cam serves the purpose of controlling the actuation of all of the pneumatically operated valves by which compressed air is admitted to the cylinders oi Me for starting, and this one cam serves t' purpose in starting the engine both in th irv'ard and revs directions. A very st le simplification of the mechanism is etlected and the adaptation of the me iisni for fora-21rd or reverse operation is accomplished by merely moving; the on v'l'iich th cam is mounted a predetermined once in axial direction,

lVhat we claim It. The conihinati n of an ernal comhusion engine h a plurality of eylinr ders, a source of supply compressed air, a pneumatically actuated air-inlet on inder controlling the pass: {c eiair id source to the cylindeiz a plurality .Ollll'lf; the supp -*-".com-

3 ir et vaivesto the L her operati ine shaft and lit rue controlling valves 'succ s for eli'ecting an adjui,

1 p I M Mitre-r, a rotzny nected to the actuate ,1 j member to vary the l ation of the air-inlet- ,'zll\ rela rotation of the engine maintaining; the rotary vrutively connected to the engine a in its adjhsteil 'pos' 'uhstuntially as described.

2. The comhin on of an internal coin hustion engine having a plurality of cylinders, a source of s'upplyot' compressed air, a pnelunatically actuated air-inlet-valve on each cylinder controlling c passage of air from said source to the at, a shatt driven by thcrehy, an aI-na h i each cylinder rontrollnug' the pas e of air from said source to the cylinder, a cam (lriicn by the engine shaft, a plurality of means ice ' pneumatically actuated air-inlet wlve on controlling valves arranged about said cam adapted to be actuated successively thereby and controlling the supply of compressed air to said inlet valves, means for holding the controlling valves normally out of coaction with the cam, and pneumatically ope rated means for moving the valves into coaction with the cam; substantiellv as ale-- scribed.

and controlling the supply of compressed air to said inlet valves, operating means for said controlling valves adapted to be actuated successively by said cam, means normally holding said operating means out of engagement with the cam, and pneumatically operated means for moving saidv operating means into engagement with the cam, substantially as described.

In testimony whereof we afiix our signatures, in presence-of txvo witnesses.

GREGORY O. DAVISON. JOHN WV. ANDERSON.

lVitnesses:

L. BRAKE, NE D. FESLER. 

